Color
Each gas, depending on its atomic structure emits certain wavelengths which translates in different colors of the lamp. As a way of evaluating the ability of a light source to reproduce the colors of various objects being lit by the source, the International Commission on Illumination (CIE) introduced the color rendering index. Some gas-discharge lamps have a relatively low CRI, which means colors they illuminate appear substantially different than they do under sunlight or other high-CRI illumination.
| Gas | Color | Spectrum | Notes | Image |
|---|---|---|---|---|
| Helium | White to orange; under some conditions may be gray, blue, or green-blue. | Used by artists for special purpose lighting. | ||
| Neon | Red-orange | Intense light. Used frequently in neon signs and neon lamps. | ||
| Argon | Violet to pale lavender blue | Often used together with mercury vapor. | ||
| Krypton | Gray off-white to green. At high peak currents, bright blue-white. | Used by artists for special purpose lighting. | ||
| Xenon | Gray or blue-gray dim white. At high peak currents, very bright green-blue. | Used in flashbulbs, xenon HID headlamps, and xenon arc lamps. | ||
| Nitrogen | Similar to argon but duller, more pink; at high peak currents bright blue-white. | |||
| Oxygen | Violet to lavender, dimmer than argon | |||
| Hydrogen | Lavender at low currents, pink to magenta over 10 mA | |||
| Water vapor | Similar to hydrogen, dimmer | |||
| Carbon dioxide | Blue-white to pink, in lower currents brighter than xenon | Used in Carbon Dioxide Lasers. | ||
| Mercury vapor | Light blue, intense ultraviolet |
Ultraviolet not shown |
In combination with phosphors used to generate many colors of light. Widely used in mercury-vapor lamps. | |
| Sodium vapor (low pressure) | Bright orange-yellow | Widely used in sodium vapor lamps. |
Read more about this topic: Gas Discharge Lamps
Famous quotes containing the word color:
“Good Hamlet, cast thy nighted color off.”
—William Shakespeare (1564–1616)
“Actors work and slave—and it is the color of your hair that can determine your fate in the end.”
—Helen Hayes (1900–1993)
“He could jazz up the map-reading class by having a full-size color photograph of Betty Grable in a bathing suit, with a co- ordinate grid system laid over it. The instructor could point to different parts of her and say, “Give me the co-ordinates.”... The Major could see every unit in the Army using his idea.... Hot dog!”
—Norman Mailer (b. 1923)